Lyapunov methods applied to multimachine transient stability with variable inertia coefficients

The paper is a contribution to the transient-stability study of multimachine power systems by Lyapunov's direct method. The mathematical model used is more rigorous than those already taken into account in that the machines' inertia coefficients are no longer considered as constant but varying with angular speed. This constitutes a more accurate approach to the transient-stability problem. A 9-machine realistic power system illustrates the proposed method, and permits comparisons and conclusions to be made.